Concrete construction



March 22, 19318. L. H. THoMAs 2311,57

I CONCRETE CONSTRUCTION Filed Nv. 22, 193s V :s sheets-sheet 1/A/vE/VTOR 1' LEONARD H. TH arms BY #my M @my O ArroR/VEX March 22,1938. L.; H. THOMAS CONCRETE CONSTRUCTION File@ Nov. 22, 1955 3'Sheets-Sheet 2 INVENTOR. LEONARD H. Flo/*ms A TTORNEY March 22, 193s.H, THOMAS l 2,111,577

CONCRETE CONSTRUCTION Filed Nov. 22, 1955 sheets-sheei 3- my n ym 7ATTORNEY.

Patented ManZZ, 1938 j I l' i .l i

-. UNITED STATES PATENT OFFICE i A y 2,111,517

coNcaE'rE coNs'raUcrIoN Leonard n.. Thomas, oakland, cam. ApplicationNovember 22,4933, Serial No. 699,161 A 4 claims (ci. 25-*121i I Theinvention relates to precast wall slabs, and Figure '11 is a section atI I--i I in Figure 9. the associated assembly of such slabs in a un-Figure 12 is a perspective view of an interlocktary structure.4 ingmeans as operative between adjacent com- An object of the invention isthe provision of a pleted slabs. generally improved and particularlyeifective Figure 13 is a vertical. section througha com- 5 means forprecasting concrete wall slabs in a pleted jointure between adjacentslabs. prone position. Figure 14 is a section at M-M in Figure 13.

Another object is to provide for a casting of As illustrated in thefragmentary view of Figthe slabs in the same relation which they are ure2, kthe present invention concerns the prol10 tohave in their finalassembly, whereby to induction and assembly of intermediate wall slabs10 sure their subsequent mutual tting at their I6 and complementarycorner wall slabs Il and jointures. I8. The slabs are cast of concreteand are cored A further object is to provide precast and cored out fromwhat may be conveniently termed their wall slabs having one sidefinished in the mold inner faces to deiine intersecting ribs I9 and 20i5 and the other side provided with means to faciliwhich provide therequisite transverse stiifness 15 tate the fixing of-a facing finishthereto. and4 effective thickness for the slabs while pro- Yet anotherobject is to provide an improved viding slabs of minimum weight. Theribs I9 reinforcing means for a slab. said means inclndprovide theequivalent of studding in the slabs, ing the aforesaid means for use infixing a facing the upper and lower ribs 2u comprise base and 'to a slabside. head plates for the slabs, and the intermediate An added object isto provide a generally imn ribs 2D provide a cross-bracing between theribs proved jointure at the abutting side edges of slabs I9 and carryelements for connecting adjacent in a structure formed therewith. slabsin an assembly thereof. Suitable reinforce- A Still further Object is toprei/ide generally ment is provided within the ribs I9 and 2li, and

improved methods for accomplishing certain of wooden furring strips 2lare shown as provided 25 the fOreSOiDg Objects# at and along the innerfaces of the ribs i9.

The invention possesses other objects and feai For casting the slabs itand il and I8 -as tures of advantage, some of which, with the foreshownand described, an horizontal and elongated going. Will be Sel; forth 0rbe apparent in the molding platform is provided, said platformparfollowing description of a typical embodiment of ticularly shownin'Figures 1 and 3 as comprising 30 the inVeIitiOf. and in theaeeempenyng dl'wjoists 22 supporting deck boards 23 thereacross ings. inwhich. Y and carried by and between side beams 24. Per- Figure 1 is afragmentary perspective view marient coremembers 25 are utilized indening illustrating a mold for use in the casting of wall. molds for theslabs; as particularly shown, the

slabs in accordance with the present invention. core members 25 aretray-like in structure and 35 Figure 2 is a. fragmentary perspectiveview generally rectangular in outline, and are adapted showing anassembly ofewall slabs embodying the for inverted application on andover the deck invention. f boards 23 with their open sides down. Tofacili- Figure 3 is an enlarged fragmentary section tate its removalfrom a cast slab, each core memtaken generally at the line 3-3 inFigure 1. and ber 25 is preferably formed with' appropriately 40thrOllBh a finished slab on the casting deck. tapering outer sideswhereby the ribs produced Figure 4 is a fragmentary perspective viewbetween opposed said sides of adjacent members teken generally at l-- inFigure 3 and Showing in the mold are narrowest at their free edges and areinforcing'means of the slab. the core members are `freely removableina well 45. Figure 5 is an enlarged section at 5--5 in Figunderstoodmanner. 45 l' ure 4. l For providingamold on the deck of the plat-Figure 6 is a perspective View Similar t0 Figform, the furring strips 2lare disposed flat thereure 4, and discloses a modification of the reinonand as spacers between core members 25 in forcing means. a desiredarrangement thereof whereby only the Figure 7 is a section at 1--1 inFigure 6. surface portions of the members above the strips 50 y Figure 8is a. fragmentary face view of a comthereat are exposed-'as bottom moldwall portions. bination partition and core member of the mold. Verticalside plates 26 are disposed on the mold Figure 9 is a section at 9`9 inFigure. deck and define the mold boundaries with their Figure 10 is afragmentary perspective view of top edges defining a reference plane forthe up- 55 the assembly of core elements shown in Figure 8.,( per ieeeQi a Casting vin the meld Form bleks 55 Cil 21 are engaged with andbetween adjacent members 25 and between the strips 2|, and other blocks28 are engaged between the side plates 26 and the sides of the members25 nearest thereto whereby the upper faces of the strips 2| and theblocks 21 and 28, and the exposed side and top faces of the members 25together, and solely, define the bottom of the moldspace provided forthe casting of a slab. The blocks 21 and l2|! are preferably, though notnecessarily, of the same thickness as the strips 2|, and the latter may,on occasion, be referred to as mold members without reference to theirpossible use as furring strips.

It will be understood that the elements 2|, 25, 21 and 23 whichcooperatively define a mold bottom are each mutually engaged against thelaterally adjacent said, elements whereby a tight mold bottom isprovided, it being noted that all of these elements are supported andheld positioned on the molding floor provided by the deck boards 23without being attached to said boards, and are therefore free for anynecessary adjustment. in an assembly thereof. In lieu of one or moremembers 25, a frame for a wall opening may be disposed on the castingdeck for keyed fixing f in the finished slab; in the present instance, awindow frame 29 is shown as set into a slab I8 which has been cast inthe mold space.

The strips 2| are secured to and mount reinforcement assemblies whichare arrQanged for desired disposal in each line of spaces betweenadjacent rows of core members 25 in which a rib I9 of a slab is to becast. As disclosed in detail in Figures 2 to 5 inclusive, the aforesaidreinforcement comprises spaced and mutually parallel bars 3| and 32connected byspaping rods 33 secured thereto. Metallic blocks 34 aresecured to each lower bar 32 at spaced points therealong, and means areprovided to releasably secure the blocks 34 of a bar 32 to a strip 2|.As shown, the blocks 34 comprise nuts threadedly receiving the shanks ofscrews 35 extending through and upwardly from the strip 2| in its centerline. Preferably, and as shown, the bars 3| and 32 lie in a plane whichincludes the center line of the strip 2|, and is perpendicular to thelower strip face. It will be noted that the blocks 34 are operative as ameans forspacing the bar 32 from the mold strip which carries it.

Upper end portions 33 of the upright'spacing rods 33may extend above thebars 3| whereby these portions may be bent downwardly over and aboutreinforcing rods 31 laid across the bars 3| for a slab, it being notedthat the plane defined by the bars 3| lies above the tops of the coremembers 25 and below the plane defined by the top edges of the sideplates 25 whereby the ba'rs 3| and rods 31 may lie within the outer wallportion of the cast slab. Preferably, and as Vindicated ln Figures 4 and5, the blocks 34 are welded tothe bars` 3l and 32, whereby to provide aunitary reinforcement assembly. 'I'he foregoing reinforcement assemblyis designed to be plant manufactured in strips which maybe cut to lengthwhereby only the wooden strips 2| need be thereafter fixed thereto forpreparing them for installation in the mold.

An alternative reinforcement assembly is illustrated in Figure 6 whereinbars 4| and 42 are held in mutually spaced relation by reason of theirengagement in spaced eyes provided in spacer elements 43 which areformed by twisting a pair of wire strands 44 about the properly spacedbars. The lower end portions f the Strands 44 are driven into oppositesides of a strip 2|', and a cross-rod 36' of the reinforcement may betied in place on a bar 4| by twisting a piece of wire about the membersat their point of mutual crossing. It will be understood that the strip2| and the rod 36' respectively correspond to the elements 2| and 36 ofthe previously described reinforcement assembly. The present type ofreinforcement assembly may also be manufactured as a stock factoryproduct for use in the disclosed manner. Y

Means are provided for directly securing adjacent wall slabs together ina structure formed therewith, a preferred jointure for mutually coplanarslabs being disclosed in detail in Figures l2 to 14 inclusive. Asillustrated, the adjacent wall slabs I6 and I3 are slightly spaced inthe assembly and tie bars and 52 extend from the exposed edges of therespective slabs for interlocking in the space defined between the slabends. The protruding ends of the bars 5| and 52 provide loops 53 whichare vertically aligned for receiving a locking bar 54transverselythrough the loops in a mannerto thereafter prevent aseparation of the slabs in their plane. Preferably, and as shown, thebars 5| and 52 are intermediately doubled to provide U-shaped loops attheir bends to provide the eyes 53 and to have the remaining portionsthereof embedded and anchored in the slabs at the ribs 20 thereof as areinforcement for the ribs. The tie bars 5| and 52 and the'locking bar54 are advantageously of square section, as is shown.

It will now be noted that the bars 5| and 52 are arranged in generallyaligned pairs whereby the eye loops 53 of a pair of bars are closetogether and mutually parallel. When the bar 54 is engaged against theinside end face 55 of one eye loop, it is arranged to be spaced from theinside end face v55 of the other eye loop of the pair, and wedge meansare provided for coaction b etween the latter end face and the bar 54 toforcibly engage the bar with the end face of the first loop and sosecure the loops againsta separation thereof and of the slabs whichcarry them. As particularly shown, the aforesaid wedge means comprises awedge 56 for engagement against the loop face 55 not engaged by the bar54, and a block 51 engaged between the wedge and bar.

. wedges 58 are applied for fixing the slabs together along theirmutually abutting edges. Preferably, and as shown, each loop 53 which isto be directly engaged by a wedge 56 is slightly curved toward thecompanion loop of a loop pair whereby theflat outer 'wedge face mayengage flat against the opposed loop face 55. The bar 54 is large enoughto be relatively stiff against flexure whereby to minimize the effect ofthe mutually offset coaction of each pair of loops 53 therewith.

It will now be noted that the slab edges at the loops 53 are formed toprovide grooves 58 along ltheir lengths, and that each said groove isdeepened at portions 59 thereof opposite the outer ends of the loops 53which extend theretoward from the opposed slab edge whereby to freelyreceive said loop endsin said groove portions. The opposed slab ends areotherwise, and correspondingly, so shaped that they are but slightlyspaced adjacent the outer slab faces, and are so spaced at and inwardlyof the loops 53 as to permit an operative disposal of the wedges 58 fromthe inner side of the slab assembly.

When adjacent slabs are mutually-interlocked along their opposed edgesby the described means, the outer and narrow portion of the space'be-` 4tween the slab ends is filled with concreteto a flush relation with theouter slab faces whereby to conceal the jointure at the latter.Subsequently, a form board-(not shown) is placed at the inner'side ofsaid space and the remainder of the space is filled with self-settingconcrete whereby a lling and sealing mass 60 is provided between theslab ends and between the wall faces. It is noted that the mass 60,through its extension into lock of the slabs.

In order to insure uniformity rof jointure and external finish forabutting slabs in an erected straight course or line thereof, the slabsare preferably cast in the same order and relation which they are tohave when they are associated as parts of a continuous structure.Accordingly, the casting deck or floor is elongated laterally of theslabs to be cast thereon whereby a succession of slabs may be producedin the order in which they are to be finally assembled. By reference tothe fragmentary showing of Figure 1, it will be noted that adjacentmolds are provided in which to cast a slab it 'and a slab 'it in thesameedge-to-edge relation and approximate spacing which the slabs vareto have when they are erected, said molds de'ned' at their opposed endsby the opposite faces of a. core member tl which partitions `the moldbox within the side plates 2t whichdefine opposite and mutually paralleledges of the molding space.

The core member 6i is seen to be shaped as the space which is to beoccupied by a filler mass til when the wall is completed in place, andextends from the deck plane to the plane defined at the top edges of theplates 24. As'particularly brought out in Figures 3, 8, 9 and l0, themember Si essentially comprises acentral plate element 62 extending forthe full core width and having plates t3 and t@ fixed to and extendinggen# erally centrally along the plate 62 at opposite sides thereof andin alternate arrangement on each side, the plates 63 and 64 beingapproximate- J ly one third as wide as theplate t2 between them.

When themember tl is installed on the mold deck, the lower edge of theelement G2 is engaged between the spacer strips 65 which in turnlaterally engage strips 2| carrying the described assemblies of ribreinforcement; vin this manner, the slabs cast in -molds at oppositesides of a core or partition 6| are produced in the rela.- tive relationwhich they are to have when erected in a structure. At that side of theplates 83 and 64 which is toward the upper mold face; the plate 62 istapered to a relatively narrow edge to provide the previously ldescribednarrow portion of the space between opposed slab ends.

In order that the core member 6I may receive the tie bar loops 53 withinthe space thereof, the central core element l! is provided with interiorslots 68 for receiving the pairs of loops 63 therein and therethrough.As particularly brought out in Figures 8 to 1i inclusive, the plates Mare generally U-shaped and are fixed and disposed on the element 62 toreceive the extremities of the loops within" their openings 61. 'Iheplates 6I at the cooperating pair of loops 53 are disposed at oppositesides of the element 62 and are oppositely directed with their open endseach receiving a loop 53. Y

A somewhat-Z-shaped metallic strip 68 ispdisposed with its centralportion between the loops of a pair, and its end portions are-xed to thedifferent plates 64 thereat for closing the outer sides of the openings61, it being noted that the plates lext'end to the central strip portionand that the width of the strip is that of the slot 66 and opening 61through which it transversely extends. The plates 63 extend betweensuccessive plates 64 at each side of the element t2 and are i notchedout at their appropriate extremities for extension through the loopthereat. Preferably, and as shown, the plates 64 are somewhat thickerthan the plates $3 transversely ofthe element 62 lvsrl'lereby the formerplates areoperative as a ,core means to denne the enlarged portions t@of the slab grooves 58, while the plates t3 dene the remaining portionsof said grooves.

It will be understood that the described core assembly 6l vis designedto completely enclose the pairs of loops of the tiebars therein wherebythe loops may extend from the cast slabs when the core assembly isremoved. The assembly of the element-62, plates tt and metal strip 6B,may be permanent, and when such assembly is placed in the describedposition on the casting deck. the

tie'bars 5i and 52 may be placed in the moldwith their loops extendinginto the core space therefor. When the tie bars have been placed, theplates 63 may be applied in their operative positions, this applicationof the plates 6d positioning and securing the loops as required. lWhenthe slabs have been cast in adjacency in the completed molds, they may,be separated in their plane to free the'partition core El. it beingnoted that the plates 63 will simultaneously be pulled from theirengagement with the element 62 with the slabs and for subsequent removalfrom the slabs.

Since thev slab l@ is a corner wall slab and is arranged for connectionwith a. slab il for providing a corner at their mutual jointure, thecorner-defining edge of this slab is appropriately bevelled for coactionwith a complementary bevelled edge of the slab il. As shown in Figures 2and 3, the said edge is arranged to make a forty-five degree angle withthe plane of the slab and is otherwise formed generally as the other endface of the slab. For defining said bevelled face of the slab I8, a moldmember H is provided at the mold end, said member comprising a plateelement l2 set at an appropriate angle to the mold bottom and carryingon its inner face plate elements which correspond to the elements t3 and6I ofthe core member 6I. Bars 'it which provide loops 63' for use lninterlocking corner slabs are so bent at said loops that the outer loopends are parallel to the`plane of the element 12, the

arrangement' permitting the use of a locking bar 54 and wedges 56 as atthe other jointures.V

Having the molds completed through the appropriete placement of thedescribed mold and reinforcement and tyingbars, the molds are filled tothe level of the tops of the side Vplates 2,8 with a suitableself-setting concrete in a plastic state. Preferably, and asparticularly indicated, the exposed slab faces 'I9 would be finished asa nal surface for the slab thereat. this being made possible by reasonof the horizontal position of such face of the mold andthe top edges ofthe plates 26 providing a screeding plane for use in applying a finishto the faces 19. With slabs so completed, their finished faces 19 mayprovide the outer facing of a building thereof without further labor.The various slabs in the described mold would preferably have theirupper faces nished together and with the same batch of grouting or otherfinish whereby the faces thereof may have a like appearance in the finalstructure. In the present instance, the mold plates 26 at the top of acast wall slab are arranged to remain on the slab, being secured theretoby means of anchor rods 8l fixed therein and embedded in the slab.

When the present slabs are erected in place, the strips 2l may be usedas a furring backing for a suitable surface finish applied thereto, ormay be removed by unscrewing the screws 35. If the strips 2l areremoved, the screws 35, or other screws, may be used to fasten otherelements to the embedded and xedly secured blocks 34 of thereinforcement assembly for each rib I9.

It will be understood that the described precasting of slabs in anhorizontal position and in a mold such as that now described facilitatesthe placement of the plastic concrete in the mold, the production ofuniform concrete structures, and the production of slabs with one nishedface; all with the use of a minimized amount of form material and labor.Furthermore, the various features of the disclosed interlock and keyingof adjacent slabs in a structure is generally .applicable tohorizontally disposed slabs as well as to "the upright wallslabs'particularly shown.' From the foregoing description, taken incon-- nection with the accompanying drawings, the advantages of theconstruction and the means for producing the same will be readilyunderstood by those skilled in the art to which the inventionappertains, and while I have described the principle of operation,together with the devices which I now consider to be preferredembodiments thereof, I desire to have it understood that the devicesshown and described are merely illustrative, and that such changes maybe made, when desired, as fall within the scope of the appended claims.

Having thus described im' invention, I claim as new and desire to secureby Letters Patent of the United States the following:

1. In combination with a mold comprising form boards defining a moldspace for the casting of a concrete body, a. pre-assembled metallicreinforcement disposed intermediately in the mold space to extend alonga said form board and including a bar, metallic spacing members fixed toand along said bar in integral relation thereto and engaged against thesaid form board, and means securing the members to the said form board.

2. In combination with a mold for casting a concrete slab to have acored face and including free core members disposed on a supportingsurface for defining ribs of said slab face between them and free formboards disposed on said surface in lateral engagement with said coremembers whereby the core members are mutually spaced and the upper facesof said boards and the face portions of the core members above the levelof said upper board faces solely define the cored face of a slab cast insaid mold, a planar metallic reinforcement assembly disposed in aribdefining portion of the mold space for embedment in a rib of theslab, spacer blocks integrally fixed to the lower edge of saidreinforcement assembly. and means coactive between the blocks and a saidform board releasably securing the board in fixed relation to thereinforcement.

3. In combination with means defining a mold space divided to provideportions thereof for the production of a plurality of separate slabs inthe space and in the order of their erection, said means including aform element fully partitioning said space at the line of abutment ofadjacent mold portions and operative as a core member to providelongitudinally grooved slab edges Vthereat whereby the grooves of theadjacent slab edges are cooperative to provide an open keying spacebetween the slabs when the completed slabs are reassociated in therelation of their casting, means providing a cavity in said element, andmutually free metallic tying members extending from the slab spaces intosaid cavity from both sides thereof for a fixing together of their freeends in the aforesaid space between the slab edges when the completedslabs are reassociated.

4. Ina mold providing a mold space divided to provide portions thereoffor the production therein of separate slabs in the space and in theorder of their erection, a form element fully partitioning said space atthe line of abutment of adjacent mold portions and operative as a coremember to provide recessed slab edges thereat whereby the recesses ofthe adjacent slab edges provide keying spaces between the slab ends whenthe completed slabs are reassociated in the relationship of theircasting, means providing a cavity in said element, and mutually freemetallic tying members extending from adjacent slab spaces into saidcavity for a xing together of their free ends in a keying space betweenthe slab edges when the completed slabs are reassoclated.

LEONARD H. THOMAS.

